Method of generating gases and treating solutions therewith



H. R. HANLILY. METHOD OF GENERATING GASES AND TREATING SOLUTIONS THEREWITH.

APPLICATION FILED APR-15,1919.

1,360,524, Patnted Nov. 30, 1920 PM PM c it c i Al rrsu'r OFFIQE.

unasnar HJNEEY, OF KENNETT,'CALIFQENI/l.

METHOD OF GENERATING GASES AND TREATING SOLUTIONS Tl-IEREWITH.

Specification of Letters Patent.

Patented My, 30, 1920.

.Application filed April 15, 1819. Serial No. 290,214.

To all ii M 7 may c0n(. -c1"n.'

lie known that l, l'liuumu'r ll. llim'cnr, a

citizen of the limited States residing at lien nets in. the county of Shasta and State of taliioruia, have invented or discovered ceitaiu new and l or (lenei'utiug (loses and Treating Solutions Tiherewith, ot which the following is it specification, reference bei had therein to the accompanying drmving.

his invention relates to the generation of particularly hydrogen sulfid, and to treatment of liquids or solutions with the gases so generutei'l for purposes of purification or otherwise. v

., The. invention has for its general objects T "l lmproveinents in Mathl the econmnic ditilizgition and complete consumption ithoutwaste of the materials used in the generation of the gas, and of the gas itself; the c .nvenient discharge oi the products of the reaction; and the thorough and even treatment of the solution to be acted upon to the desired extent Without local over-treatment or removal therefrom of substances not intended. 1/

The tore roin and other ob'ects of the i, t" l invention, together with means whereby the some may be carried into effect, will best be understood from the following description of one form of apparatus embodying the in veution and capable of operation in accord once. with the method involved. it will be vu oderstood, however, that the particular con-- structions, arrangements, and operations referred to have been chosen. for illustrative piuposes merely, and that the invention, as defined may be otherwise practised Without departin from the spirit and scope thereof.

in said ell-swin Figure l is diagremnmtic view of an up peratus arrangcll in accordance with the invention.

. if 2 is i drum.

an end elevation of the generatlion of certai upon a solidresgent, :1 the. geueratii'iu l hydrogen sulvell known reaction between iron .il bearing bodies and acids, it is hat, the action proceeds, the rate neration becomes erzulually retardseslihg; over of the active solids products of the reaction. and llnnll'v the generation ceases before of the reagents has been completely by the claims hereunto appended,

consumed. It has also been found that the pressure developed by the gases as generated cannot be depended upon. to force such gases through the solutions to be treated, particularly when the generating reaction becomes Weak as the acid approaches neutralization, and that, indeed, 1n order to secure efficient gas generation, it is necessary to avoid any gas pressure Whatever Within the generator.

of air is established through the apparatus in such a manner as to cause the gas to be (1 'ur vn from the generator as fast as it is formedand to pass through the solution to be treated irrespective of the absence of ,driving; pressure behind it in the generator To these ends the generator as shown com- Jl'lSQS a cylindrical vessel 10 preferably composed of Wooden stoves and lined :With lead. The lead lining is preferably protected from abrasion by an inner Wood covering. The

outside wood stoves are held together by the usual hoops or bands ll. In addition to the hoops, there are circular rails of suitable cross section fastened to the drum and constituting a circular track. The cylinder or drum 10 is mounted upon wheels 12 upon which the rails or hoops 11 rest, said rails or hoops constituting a circular track Whereby said drum may readily rotated upon said WhGPlS, as by means of a sprocket chain 13 engaging a suitable toothed ring 14 carried by said drum adjacent one end. Said drum ll) 1 provided with an opening or manhole normally closed by a suitable cover and through. which the activo solids are introduced and the inert residue d1s charged, with an axial inlet 16 tor (hi5 ELClCl or other active liquid, and with an axial outlet 17 for the gas generated; The active solids, in more or less broken or finely db vided form, may be supplied from a hopper or receptacle 18 having a chute 19 adopted,

'When the drum 10 is in the position shown in Fig. l and the manhole cover removed, to discharge the desired quantity of said solids through said manhole into the interior of the drum. The acid or other active liquid may be stored in a tank 20 having a valve controlled outlet 21 from which leads a pipe 22 communicating with a second pipe. 23 leading to the inlet 16. Beneath the wheels 12 is a hopper 24 adapted to direct material discharged from the drum 10 into a suitable receptacle or car 25, whereby said material may be disposed of in any desired way.

In operation, the necessary reagents hav ing been supplied to the drum 10 from the receptacle 1S and tank 20, respectively, the manhole cover 15 is replaced and the reaction allowed to proceed in the usual manner, the gas generated passing out of the drum through the outlet 17. When the genera tion of gas begins to be retarded, due to the coating of the active solids with inert matter, the drum is rotated more or less to cause the solids to fall about therein, thereby causing the inert coatings to be removed by attrition, and new surfaces to be presented to the liquid reagent. As the reagents approach exhaustion'the drum may be rotated constantly until the acid has been completely consumed or neutralized. Thereafter the cover 15 may be removed, the drum turned to bring themanhole lowermost, and thewaste material thereby conveniently discharged through the hopper 24 into the car or other receptacle 2:").

In accordance with the present invention, the acid used is of such dilution that it will not dissolve or combine with more of the metallic constituent of the active solid than, when combined with the acid radical to form the resultant neutral salt, will be retained in solution in the liquid present without crystallization. Taking, by way ofexample, the generation. of hydrogen sulfid by the action of sulfuric acid upon iron sulfid, if the usual strong or relatively concentrated acid is used, say 300 grams of sulfuric acid per liter of liquid, thisacid will be capable of dissolving or combining with 17 0 grams of iron per liter. The generator solution, however, can carry only 144 grams of iron per liter, which will enter into combination with only 252 grams of sulfuric acid per liter. The generator solution there fore carries an excess of 48 grams of sulfuric acid per liter at the time said solution is saturated with iron, which means that no further reaction will be possible unless the process is interrupted and water introduced to furnish suflicient liquid to dissolve the iron capable of combining with the remaining 48 grams of sulfuric acid. This will.

cause a waste of gas. 1n accordance with the present invention, howeventhe acid solution is introduced at such a strength,

say, in the example above given, 200 grams of sulfuric acid per liter, that the amount of iron capable of combining therewith will be easily retained in the generator solution at neutrality. In other words, in accordance with the present process, the acid is-diluted to such a proportion that the total quantity of liquid is sufficient to retain in solution the product of the reaction when the acid in the said liquid is completely consumed. I I

From the gas outlet 17 the gas is conveyed to the treating or precipitating tank or chamber 26 in which the solution to be purified or otherwise treated is placed. In the preferred arrangement shown the outlet 17 communicates with a pipe 27 leading to aseparator 28 in which any moisture carried by the gas is removed and from which leads a pipe 29 by which the gas is conveyed to a washer 30 from which said gas passes through a pipe 31 to said treating tank or chamber 26. At some point in the system is provided a pump or suction device whereby a circulation of gas is established and a condition of partial vacuum maintained in the generating drum 10, said device, as here in shown, comprising a blower 32 in the piping 81. The pipe 31 communicates with suitable perforatpd inlet member Said tank or chamber 26, which is fitted with a closed top, has superimposed thereon a drum 34: communicating with the interior of the tank. The gas, after passing through the solution in the tank, enters the drum 34, carrying with it the froth or foam formed by the action of the gas on the solution, said froth or foam being separated from the attenuated gas in said drum, and'tlie solid particles in suspension returning by gravity to the tank. Leading. from the separating drum 34 is a pipe 35 through which a portion of the attenuated or partially spent gas is returned to the generating amber or drum 10, where it is mixed with' the freshly generated gas and again conveyed to the treating tank being therelijwegener ated and rendered capable of further actionupon the solution to be treated. The pipe 35 preferably leads to a separator 46 in which the gas is relieved of any moisture I taken up during its passage through the precipitating tank 26 and separating drum 34, and from which said gas passesthrough a pipe 47 to the liquid inlet pipe 23 and thence to the drum 10 by way of the inlet 16. In thismanner it will be seen that a It has been observed that, when gas is closed circuit between the generating chamiseo introduced into a liquid, the greatest agitation or the l quid occurs a short distance above the level at which said gas 12 introduced, but since vigorous agitation is neces- 36 being provided with a blower or other circulating incans 38, whereby a portion of the attenuated or partially spent in the 1 n returnei'l to the tank 2-6. The at teuuatcd gas which thus enters the trmitinutan below the inlet 33 produces, at short we above the inlet 37, and consequently in the vicinity or none of the inlet 33, a violent agitation. It will thus be seen that the richer gas from the inlet 33 enters the solution at a point where violent agitation of the occurs, which disperses said richer through very large volume of the solution, thereby insuring a relatively even treatment of the solution by the gas.

This is highly dez iblc, particularly in the use of hydrogen s ltid as purifying agent, since when said isuntroduced into the solution Without additional agitation said solution is frequently locally overtreuted. For example, hydrogen suliid is frequently used for the purpose of removing arsenic, copper, cadmium and other impurities from the solutions of Zinc sulfate. Overtroatmcnt will result in the removal also of a greater or less amount of the zinc, which is objectionable but diliicult to avoid in apparatus asheretofore arranh'ed, and in which the gas is not thoroughly dispersed throughout the liquid, since treatment sullicient to remove all impurities from all parts of the mass will, be greater than necessary in some parts. reason of the thorough dispersion of the gas in the arrangement above describechsaid may be caused to remove the desired impurities Without affecting the constituents to be retained.

In order to'insure the maintenance of the desirable condition of partial vacuum within the system and prevent the pressure therein from rising above a predetermined maximum, due to inward air leakage or otherwise, means are preferably provided for automatically discharging from the system any excess pressure developed therein, said means being of such a character as fully to utilize the discharged so as to prevent wastage thereof. :isherein shown a third pipe 39 is led from the separating drum 3-1, said pipe being provided with a blower or othercirculating means l0 and with a relief or check valve ll edaptcd when the mined maximum, to open and permit a por-' tion of the attenuated in the separating I drum 34: to be drawn through the pipe 39 by the blower lO. In order that the gas thus drawn through the pipe 39 may be con'ipletely utilized or exhausted, thereby also avoiding any danger or deleterious efliect due to the discharge of even a highly attenuated gas into the atmosphere, said gas maybe forced by the blower 40 through a pipe 4-2 to a secondary or auxiliary precipitatino; or trout/inn tank or chamber 4.3, said enterinobztkl tank or chamber through a suitable inlet 41 1-, and being discharged to the atmosphere through a suitable exhaust pipe As a further siiiteguard against the dcvclopment of pressure in the generating:

chamber 10, due to accidental obstruction of the system at some point,'or otherwise. the separators 28 and 4-6 are preferably provided with water seals 50 and 51 adapted to be blown oil in the event of excess pressure. thereby venting said pressure to the atmosphere.

l do not herein claim the apparatus hereinbeiorc described, the same is claimed in my application Serial No. 337,676, filed November 13-, 1919, which is a division of this application.

Having thus described my invention I claim and desire to secure by Iietters Patent:

1. The herein described method of treating liquid with gas, which consists in introducing the gas into the liquid at a given level, collecting the partially spent gas above the surface of said liquid, and again introducing the same into said liquid at a level beneath said first-named level.

2. The herein described method of treating liquid with gas, which consists in intro ducing the gas into the liquid at a given level, separating the resultant froth from the partially spent gas, and again introdu'cing said partially spent gas into said liquid a level beneath said first named level.

3. The herein described method of generating, gases and treating solutions therewith, which consists in bringing together in a generating chamber and under the required conditions the necessary materials to bring about the gas generating reaction, passingthe resultant through the solution to be treated in a treating chamber, and thereafter returning the partially spent gas to said generating chamber and mixing the same with fresh gas for further use.

4:. The herein described method of gcnen sting gases by'the action of an acid upon a reagent and treating solutions With the gas so generated, which consists in diluting the acid to such a proportion that the quantity of liquid is sufiicient to retain in solution the product of the reaction when the acid in said liquid is completely consumed, treating said reagent with said liquid in a generating chamber passing the resultant gas through the solution to be treated in a treating chamber, and returning the partially spent gas to said generating chamber.

5. The herein described method of generating gases and treating solutions therewith, which consists in bringing together in a generating chamber and under a condition of partial vacuum the necessary materials to bring about the gas generating reaction, passing the resultant gas through the soln tion to be treated, and thereafter returning the partially spent gas to said generating chamber and mixing the same with "fresh gas for further use.

(3. The herein described method of generating gases and treating solutions therev 1th, which consists in bringing together in a gen erating chamber the necessary materials to bring about the gas generating reaction, maintaining a condition of partial vacuum in said chamber. passing the resultant gas through the solution to be treated, and causing the partially spent gas to return to said generating chamber under the influence of said partial vacuum.

7. The herein described method of generating gases and treating solutions therewith. which consists in bringing together in a generating chamber the necessary materials to bring about the gas generating react on, applying suction to said chamber to draw the resultant gas therefrom and forcing said gas through the solution to be treated in a treating ehamber.. thereby maintaining condi tions of relatively low and high pressures in said generating and treating chambers, and causing the partially spent gas, under the influence of said differences in pressure, to return to said generating chamber.

8. The herein described method of generating gases and treatin solutions therewith, which consists in bring g together in a gencrating chamber the necessary materials to bring about the gas generating reaction, passing the resultant gas through the solution to be treated, and thereafter returning a portion oi the partially spent gas to said generating chamber and mixing the same with fresh gas for further use.

9. The herein described method of generating gases and treating solutions therewith, which consists in bringing together in a generating chamber the necessary materials to bring about the gas' generating reaction, passing the resultant gas through the solution to be treated, returninga portion of the partially spent gas to said generating chant her and mixing the same with fresh for further use and again introducing the remaining portion of said spent gas into said solution.

10, The herein described method of generating gases and treating liquids there- I with. which consists in bringing together in.

a generating chamber the necessary materials to bring about the gas generating reaction, introducing the as so generated. into the liquid in a treating chamber at a level above the bottom thereof, collecting the partially spent gas above-the surface of said liquid, returning a portion of the gas so collected to said generating chamber, and again introducing another portion of said gas into said liquid at a level beneath said first named level.

In testimony whereofI afiix my signature.

manner a. nastier. 

